Abstract: A demodulation reference signal port mapping method is disclosed. The method includes: a base station communicates with a User Equipment (UE), and allocates corresponding data stream to the UE according to the attribution of the UE; the base station maps the corresponding data stream from a layer to a corresponding demodulation reference signal port; the base station transmits the corresponding data stream to the UE via demodulation reference signal port. By restricting the demodulation reference signal port mapping solution of rank=1 to rank=8 and the demodulation reference signal port mapping solution when the retransmission occurs, the technical solution enables the demodulation reference signal port mapping solution to compatible with the present system and to keep lower overhead of the demodulation reference signal.

Abstract: A method and a system for coordinated transmission, and a mobile terminal and network side device are provided. The method for coordinated transmission includes: reporting by the terminal of a signal measurement result; determining the coordinated transmission state of the terminal according to the signal measurement result; and providing transmission service for the terminal according to the determined transmission state.